Intravenous drug using clients of a Dublin HIV Prevention Unit were interviewed about their use of general practitioner services. Sixty eight percent of clients had visited a GP within the previous year and 48% were registered with a GP under the General Medical Services (GMS) Scheme. Of 161 interviewees 60 were being treated with a fixed dose regimen of methadone at the Prevention Unit; this group was far less likely to visit a GP with a drug related problem and far less likely to have received methadone from a GP. Members of the GMS were much more likely than non members to have visited a GP and also more likely to have attended a specific GP for all problems besides methadone treatment. Methadone treatment and medical cover within the GMS Scheme emerged as important influences on the behaviour of clients with respect to general practitioners.